Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm running a shared hosting environment with about 100 sites - I just took a peek at all the modules apache is loading/using, some of these I don't know what they are or do or if they are useful at all...

core_module (static)
 mpm_prefork_module (static)
 http_module (static)
 so_module (static)
 unique_id_module (shared)
 auth_basic_module (shared)
 auth_digest_module (shared)
 authn_file_module (shared)
 authn_alias_module (shared)
 authn_anon_module (shared)
 authn_dbm_module (shared)
 authn_default_module (shared)
 authz_host_module (shared)
 authz_user_module (shared)
 authz_owner_module (shared)
 authz_groupfile_module (shared)
 authz_dbm_module (shared)
 authz_default_module (shared)
 include_module (shared)
 log_config_module (shared)
 logio_module (shared)
 env_module (shared)
 ext_filter_module (shared)
 mime_magic_module (shared)
 expires_module (shared)
 headers_module (shared)
 usertrack_module (shared)
 setenvif_module (shared)
 mime_module (shared)
 dav_module (shared)
 autoindex_module (shared)
 dav_fs_module (shared)
 vhost_alias_module (shared)
 negotiation_module (shared)
 dir_module (shared)
 actions_module (shared)
 speling_module (shared)
 userdir_module (shared)
 alias_module (shared)
 rewrite_module (shared)
 cache_module (shared)
 suexec_module (shared)
 disk_cache_module (shared)
 file_cache_module (shared)
 mem_cache_module (shared)
 cgi_module (shared)
 version_module (shared)
 fcgid_module (shared)
 google_sitemap_generator_module (shared)
 jrun_module (shared)
 deflate_module (shared)
 evasive20_module (shared)
 perl_module (shared)
 php5_module (shared)
 ssl_module (shared)

Are there any there that can be removed to try and minimize apaches memory footprint, or are these all pretty much required?

[I installed evasive, deflate, jrun, google & unique_id - so those ones are staying.]


I think I need to clarify my question a little more;

If anyone sees any modules in there that are generally not used or useful in a shared hosting environment, please let me know which ones so I can dig further and see if they are actually in use. My problem is that even reading what the modules do from apache sometimes doesn't give many clues as to what the impact of removing it may be. For example: logio_module - reading - it seems to be pretty much un-needed. though, does it mean that the file size in my logs will suddenly disappear? or worse yet, break logging altogether?

share|improve this question

Well, which ones are you (and your users) using? You're the only one that can answer that.

There's no harm in disabling a module to see if something breaks. You can just easily re-enable. Better yet, test disabling modules on your development server (you have one of these, right?). If all goes well, disable on the prod server as well.

share|improve this answer
hard to say, as I said it's shared hosting, so it's anyone's guess what ~may~ be in use. some of them are pretty obviousto leave be [mime, headers, expires] but others, not so sure.... speling_module, negotiation_module ??? no clue. – Sean Kimball Sep 13 '11 at 2:08
Well there no possible way that I nor anyone else here can tell you what to disable. – EEAA Sep 13 '11 at 2:08
this is a shared server with over 100 sites on it, maintaining a dev environment to see if anyone else's applications break is not a viable option - There is great harm in turning off modules & taking a chance that it breaks a clients application, that is a horrible idea. My question was I don't know what a good deal of these do - if you see something generally useless in a shared type environment, let me know & I can dig further. – Sean Kimball Sep 13 '11 at 2:39
There is no such thing as a "typical" shared environment. All you need to do is look up the documentation for each module. Apache documentation is very good. Just Google "mpm_prefork_module" (for instance) and read up on its functionality. (Hint: you probably don't want to disable that one) – EEAA Sep 13 '11 at 2:43
Hi ErikA - i just updated my question a bit, hopefully it clarifies somewhat. I agree Apache documentation is excellent, however generally does not offer much beyond the nuts and bolts [see my "what is the impact" statement] - prefork... heheh, yea, I kinda figured that would be required ;) – Sean Kimball Sep 13 '11 at 2:50

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.